Fireman&#39;s ladder



Feb. 14, 1939. A. HUMMEL FIREMANS LADDER Filed Oct. 16, 1957 2 Sheets-Sheet l Invenfor:

FIREMAN S LADDER Filed Oct. 16, 1957 2 Sheets-Sheat 2 zzzztzz Fig. 5

Patented Feb. 14, 1939 UNITED STATES PA TENT 5 OFF I'CIE FIREMANS LADDER many Application October 16, 1937, Serial No. 169,353 In Germany October 14, 1936 12 Claims.

The invention relates to a multiple section extensible firemans ladder with shaped metal side bars.

Multiple section extensible ladders are known in which the side bars .are' open channel beams.

These known side bars consist of single or builtup rolled channels. In contrast to these the side bars according to the present invention are constituted by shaped metal pieces which can be produced in a' very simple way by bending, rolling, or pressing sheet metal. Particularly in production by bending the manufacturer is decidedly freer in the choice of dimensions than in production by rolling from solid ingots, because special mills are not required for each size. This is important for ladder side bars, because it is very much desired, for reduction of weight, to make each ladder section with somewhat smaller dimensions than the one below it, corresponding to the smaller load which it carries. This requires as many difierent shapes as ladder sections.

It is true that ladder side bars are known having a U-shaped cross section and which can be made of sheet metal. However, these are not adapted without special auxiliary devices for making ladders with more than two sections.

By this invention there is provided for the first time a shaped metal beam for ladder side bars which can be produced from sheet metal by bending, rolling or pressing and also can be used for ladders of more than two sections. The shaped metal beam consists of a relatively high vertical web and a relatively broad horizontal flange, considering the beam as lying in the position it assumes when the ladder is in a horizontal position with the sections for the higher part of the ladder above the lower sections. By

this form there is imparted to the shaped metal beam a high resistance to bending, in vertical as well as in horizontal direction, which can be considerably increased by a special fastening arrangement for the struts and diagonal braces of the truss structure. In the lower part of the shaped metal beam there is then produced-a sort of closed shape, so that by this invention the advantages of the open shape arecombined with those of the closed shape. The shaped metal beam has the further advantage that the height of the ladder, considered in its horizontal'position, remains small and that by an exceptionally favorable utilization of space all the guide rollers can be arranged on the-ladderv side bars, that is, on the basic supporting structure.

In the drawings, wherein one example of a four-section ladder embodying the invention is shown,

Fig. 1 is a side view of a portion of the ladder;

Fig. 2 is a cross section on theline 2'-2 of Fig. 1;

Fig. 3 is a cross section on the line 3-3 of Fig. 1;

Fig. 4 is a cross section on the line 4-4 of Fig; 1;

Fig. 5 is a cross sectional view of one of the side bars of the ladder, showing its construction from standard constructional sheet metal; and

Fig. 6 is a perspective view oftwo sections of ladder, with parts cut away.

The open shaped metal beam which constitutes the sidebar and is roughly of 8 form is so arranged that the upper opening of the S is directed inward. The beam consists of an upper horizontal flange I, which may be single, or, as shown in the drawings, doubled over to form a strengthening bead; a vertical web 2 connected to the flange I; and a lower horizontal flange 3 at the bottom of the web 2; The shape then turns downward, forming a second vertical web 4 and united with this web a horizontal outwardly directed flange 5. The latter terminates at its outer edge in a roll 6, which can be open or closed and which, as shown in the drawings, has a downwardly directed vertical face and an inwardly directed horizontal face. The upper inwardly opening part I, 2, 3 of the S-shape is higher than the lower part of the S-shape and serves to receive guide rollers H and I3 of the next higher ladder section, which is guided in the side bars.

The" horizontal flange 5 of the shaped metal beam serves as a guide surface for bearing rollers l, which are mounted upon the side bars or the'rungs 9- byplates 8 (Fig. 2). These rolls can'also be made in known manner as double swing rollers. They are preferably distributed along the whole'length of the ladder section.

'I'he'horizontal flange 3'serves as a rest for the rungs 9, which are secured theretoypreferably by welding. The'upper flange l serves as a guide surface forthe rollers H (Fig. 4) mounted on the foot of the outer side of the side bar of the next higher section by brackets Hl.- At this place the horizontal flange 5 androll G of the side bar of the guided section are cut out back to the intersection of the plane of the vertical web 2 with the horizontal web 5, in order to make possible the fastening of the bracket HI and provide space for the rollers l I.

On the foot of the guided section there are further provided on the outside of the vertical web 2 bearing blocks l2, which carry the rollers l3 (Fig. 3) for the lateral guiding. These rollers roll against the inner side of the vertical web 2 of the side bar of the next lower section and ex tend inward into the space enclosed by the parts 3, 4 and 5 of the shaped metal beam.

On the top part of each guiding ladder there are mounted, on the outside of each vertical web 2 of the side bar, bearing blocks M, which carry rollers l5 for the lateral guiding of the next higher ladder section. These rollers extend through holes in the web 2 and roll upon the outer vertical surface of the roll 6 of the next higher ladder section (Fig. 2).

. On the outer side of the S-shaped side bar are truss struts and diagonal braces l6 supporting a tension rod l1. These struts and braces rest against the vertical web 2 of the side bar, being preferably welded thereto, and extend downward to the horizontal flange 5, to which they can also be secured, so that a good stiffening of the S- shaped beam is obtained. These struts and diagonal braces, which have been omitted from Figs.

13 and 4 to avoid confusion, are secured to the upper tie rod l1. They can be in the form of open or closed structural pieces. Besides these struts or braces 16 there may also be additional members serving only to stiffen the side bar,

these being welded in a similar manner to the side bar.

The relation of the lengths of the individual parts of the shaped metal beam to one another is not limited to that shown in the drawings, but can .lwbe changed according to the size of the ladder and and Z beams, for instance, in the manner shown in Fig. 5.

I claim:

1. An extensible ladder composed of relatively slidable sections, each section comprising side bars of shaped metal, each side bar being composed of a single vertical web with inwardly projecting flanges at top and bottom, the bottom flange having connected thereto a horizontal flange projecting outward beyond the plane of said vertical web, guiding means on each section except the bottom one bearing against the top inwardly projecting flanges of the side bars of the next lower section, guiding means on each section except the top one bearing against the outwardly projecting flanges of the side bars of the next higher section, and rungs resting against and secured to the bottom inwardly projecting flanges of the side bars of each section.

2. An extensible ladder composed of relatively slidable sections, each section comprising side bars of shaped metal, each side bar being composed of a single vertical web with inwardly projecting flanges at top and bottom, the bottom flange having connected thereto by a second vertical web a horizontal flange projecting outward beyond the plane of said first vertical web, guiding means on each section except the bottom one bearing against the top inwardly projecting flanges of the side bars of the next lower section, guiding means on each section except the top one bearing against the outwardly projecting flanges of the side bars of the next higher section, and rungs resting against and secured to the bottom inwardly projecting flanges of the side bars of each section.

3. An extensible ladder composed of relatively slidable sections, each section comprising side bars of shaped metal, each side bar being composed of a single vertical web with inwardly projecting flanges at top and bottom, the bottom flange having connected thereto a horizontal flange projecting outward beyond the plane of said vertical web, and provided at its outer edge with a stiffening roll, guiding means on each section except the bottom one bearing against the top inwardly projecting flanges of the side bars of the next lower section, guiding means on each section except the top one bearing against the outwardly projecting flanges of the side bars of the next higher section, and rungs resting against and secured to the bottom inwardly projecting flanges of the side bars of each section.

4. An extensible ladder composed of relatively slidable sections, each section comprising side bars of shaped metal, each side bar being composed of a single vertical web with inwardly projecting flanges at top and bottom, the top flange being recurved to form a strengthening bead, the bottom flange having connected thereto a horizontal flange projecting outward beyond the plane of said vertical web, guiding means on each section except the bottom one bearing against the top inwardly projecting flanges of the side bars of the next lower section, guiding means on each section except the top one bearing against the outwardly projecting flanges of the side bars of the next higher section, and rungs resting against and secured to the bottom inwardly projecting flanges of the side bars of each section.

5. An extensible ladder composed of relatively slidable sections, each section comprising side bars of shaped metal, each side bar having a vertical web with inwardly projecting flanges at top and bottom, the bottom flange having connected thereto a horizontal flange projectingv outward beyond the plane of said vertical web, tie members extending longitudinally of the side bars of each section, struts between said tie members and side bars fastened to the vertical webs of the side bars and extending down to the outwardly projecting flanges of said side bars, guiding means on each section except the bottom one bearing against the top inwardly projecting flanges of the side bars of the next lower section, guiding means on each section except the top one bearing against the outwardly projecting flanges of the side bars of the next higher section, and rungs resting against and secured to the bottom inwardly projecting flanges of the side bars of each section.

6. An extensible ladder composed of relatively slidable sections, each section comprising side bars of shaped metal, each side bar being composed of a single vertical web with inwardly projecting flanges at top and bottom, the bottom flange having connected thereto a horizontal flange projecting outward beyond the plane of said vertical web, guiding means on each section except the bottom one bearing against the top inwardly projecting flanges of the side bars of the next lower section, guiding means on each section except the top one bearing against the outwardly projecting flanges of the side bars of the next higher section, and rungs resting against and secured to the bottom inwardly projecting flanges of the side bars of each section, the height of said vertical web being approximately equal to the sum of the vertical dimensions of a rung and the guiding means which bears against the top inwardly projecting flange.

7. An extensible ladder composed of relatively slidable sections, each section comprising side bars of shaped metal, each side bar having a vertical web with inwardly projecting flanges at top and bottom, the bottom flange having connected thereto a horizontal flange projecting outward beyond the plane of said vertical web, guiding means on each section except the bottom one bearing against the top inwardly projecting flanges of the side bars of the next lower section, guiding means on each section except the top one bearing against the outwardly projecting flanges of the side bars of the next higher section, guiding means on each section except the bottom one bearing against the inner surface of the vertical webs of the side bars of the next lower section, and rungs resting against and secured to the bottom inwardly projecting flanges of the side bars of each section.

8. An extensible ladder composed of relatively slidable sections, each section comprising side bars of shaped metal, each side bar having a vertical Web with inwardly projecting flanges at top and bottom, the bottom flange having connected thereto by a second vertical web a horizontal flange projecting outward beyond the plane of said first vertical web, guiding means on each section except the bottom one bearing against the top inwardly projecting flanges of the side bars of the next lower section, guiding means on each section except the top one bearing against the outwardly projecting flanges of the side bars of the next higher section, guiding rollers on each section except the bottom one bearing against the inner surfaces of said first vertical webs of the side bars of the next lower section and partly housed between the bottom inwardly projecting flanges and the outwardly projecting flanges of the side bars of the section on which they are mounted, and rungs resting against and secured to the bottom inwardly projecting flanges of the side bars of each section.

9. An extensible ladder composed of relatively slidable sections, each section comprising side bars of shaped metal, each side bar having a vertical web with inwardly projecting flanges at top and bottom, the bottom flange having connected thereto a horizontal flange projecting outward beyond the plane of said vertical web, and provided at its outer edge with a roll having a downwardly directed vertical face and an inwardly directed horizontal face, guiding means on each section except the bottom one bearing against the top inwardly projecting flanges of the side bars of the next lower section, guiding means on each section except the top one bearing against the outwardly projecting flanges of the side bars of the next higher section, guiding rollers mounted on the outer faces of the vertical webs of the side bars of each section except the top one and extending through holes in said vertical webs to bear against the downwardly directed vertical faces of the rolls on the outwardly projecting flanges of the side bars of the next higher section, and rungs resting against and secured to the bottom inwardly projecting flanges of the side bars of each section.

10. An extensible ladder composed of relatively slidable sections, each section comprising side bars of shaped metal, each side bar being essentially composed of a single broad vertical web and a single broad horizontal web integral therewith, said webs being braced by struts fixed to the outer side of said vertical web and the upper side of said horizontal web, said vertical web having an inwardly directed flange at the top, guiding means on each section except the bottom one bearing against the lower side of the inwardly projecting flanges at the top of the vertical webs of the side bars of the next lower sections, guiding means on each section except the top one bearing against the lower side of the horizontal webs of the side bars of the next higher section, and rungs secured to said side bars.

11. An extensible ladder composed of relatively slidable sections, each section comprising side bars of shaped metal, each side bar having a vertical web with inwardly projecting flanges at top and bottom, the bottom flange having connected thereto a horizontal flange projecting outward beyond the plane of said vertical web, struts fixed to the outer sides of said vertical web and to the upper side of said outwardly projecting flange, guiding means on each section except the bottom one bearing against the top,

inwardly projecting flanges of the side bars of the next lower section, guiding means on each section except the top one bearing against the outwardly projecting flanges of the side bars of the next higher section, and rungs resting against and secured to the bottom inwardly projecting flanges of the side bars of each section.

12. An extensible ladder composed of relatively slidable sections, each section comprising side bars of shaped metal, each side bar having a vertical web with inwardly projecting flanges at top and bottom, the bottom flange having connected thereto a horizontal flange projecting outward beyond the plane of said vertical web, struts fixed to the outer sides of said vertical'web and to the uper side of said outwardly projecting flange, guiding means on each section except the bottom one bearing against the top inwardly projecting flanges of the side bars of the next lower section, guiding means on each section except the top one bearing against the outwardly projecting flanges of the side bars of the next higher section, and rungs secured to said side bars.

ADOLF HUMMEL. 

